There are numerous varieties of fluid filled surgical implants presently comprising, or which may in the future comprise, access ports, for hydraulically adjustable gastric bands.
An exemplary hydraulic adjustable gastric band comprises a saline solution inside of one or more inflatable portions (e.g., silicone shells) positioned on the stomach surface of the ring of the gastric band to adjust the gastric band through a variety of diameters. As the inflatable portion is inflated it reduces the stoma of the gastric band and when the inflatable portion is deflated it increases the stoma of the gastric band. The saline solution is added to or removed from the inflatable portion via an access port fixed beneath the skin of the patient in the abdomen on the rectus muscle sheath using a fine needle to find the right level of restriction.
An exemplary gastric band (hydraulic, hydraulic-mechanical hybrid, or otherwise) may additionally, or alternatively, comprise an access port coupled with an override mechanism to rapidly remove fluid or gel from the implant in the event of an emergency.
Each of the foregoing implants, as well as others, comprise access ports that may be candidates for various electronics based enhancements, e.g., an access port fitted with a pressure sensor and/or an access port that transmits a signal for easier detection of its location within the body of the patient.
By way of example of the latter, it is essential with a hydraulic adjustable gastric band that the orientation of the implanted access port allows fluidic contact with the Huber needle of the syringe. In other words, the septum of the implanted access port should ideally be parallel to the plane defined by the surface of the patient's skin above the septum of the implanted access port. However, it is possible for the implanted access port to tilt from the ideal orientation resulting in less surface area for fluidic contact with the Huber needle. Thus, there is a need for tilt detection, communication, and compensation for fluid filled surgical implants.
Ferreri et al. (U.S. Pat. No. 7,658,196) discloses a system operable to detect the orientation of an implant component. Ferreri discloses that a sense head can be moved around a patient's body to determine a location of the implanted access port using, for example, triangulation. However, Ferreri does not disclose that the tilt detection occurs at the sense head by moving a sense head to a location of the center of the port. Thus, a user must scan a large area of the patient's body in order to determine the tilt of the implanted access port. This can be embarrassing to the patient, and inconvenient to the patient, and/or time consuming.